﻿// This file is part of the WinFormedge project.
// Copyright (c) 2025 Xuanchen Lin all rights reserved.
// This project is licensed under the MIT License.
// See the LICENSE file in the project root for more information.

namespace WinFormedge.WebResource;

/// <summary>
/// Abstract base class for handling web resources in the WinFormedge project.
/// Provides MIME type mapping and request handling logic.
/// </summary>
public abstract class WebResourceHandler
{
    #region MineTypeMap
    // From https://github.com/samuelneff/MimeTypeMap
    /*
        The MIT License (MIT)

        Copyright (c) 2014 Samuel Neff

        Permission is hereby granted, free of charge, to any person obtaining a copy
        of this software and associated documentation files (the "Software"), to deal
        in the Software without restriction, including without limitation the rights
        to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
        copies of the Software, and to permit persons to whom the Software is
        furnished to do so, subject to the following conditions:

        The above copyright notice and this permission notice shall be included in all
        copies or substantial portions of the Software.

        THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
        IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
        FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
        AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
        LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
        OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
        SOFTWARE.
     */
    /// <summary>
    /// Provides mapping between file extensions and MIME types.
    /// </summary>
    static class MimeTypeMap
    {
        private const string Dot = ".";
        private const string QuestionMark = "?";
        private const string DefaultMimeType = "application/octet-stream";
        private static readonly Lazy<IDictionary<string, string>> _mappings = new Lazy<IDictionary<string, string>>(BuildMappings);

        /// <summary>
        /// Builds the dictionary of file extension and MIME type mappings.
        /// </summary>
        /// <returns>A dictionary mapping extensions to MIME types and vice versa.</returns>
        private static IDictionary<string, string> BuildMappings()
        {
            var mappings = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase) {

                            #region Big freaking list of mime types
                        
                            // maps both ways,
                            // extension -> mime type
                            //   and
                            // mime type -> extension
                            //
                            // any mime types on left side not pre-loaded on right side, are added automatically
                            // some mime types can map to multiple extensions, so to get a deterministic mapping,
                            // add those to the dictionary specifically
                            //
                            // combination of values from Windows 7 Registry and 
                            // from C:\Windows\System32\inetsrv\config\applicationHost.config
                            // some added, including .7z and .dat
                            //
                            // Some added based on http://www.iana.org/assignments/media-types/media-types.xhtml
                            // which lists mime types, but not extensions
                            //
                            {".323", "text/h323"},
                            {".3g2", "video/3gpp2"},
                            {".3gp", "video/3gpp"},
                            {".3gp2", "video/3gpp2"},
                            {".3gpp", "video/3gpp"},
                            {".7z", "application/x-7z-compressed"},
                            {".aa", "audio/audible"},
                            {".AAC", "audio/aac"},
                            {".aaf", "application/octet-stream"},
                            {".aax", "audio/vnd.audible.aax"},
                            {".ac3", "audio/ac3"},
                            {".aca", "application/octet-stream"},
                            {".accda", "application/msaccess.addin"},
                            {".accdb", "application/msaccess"},
                            {".accdc", "application/msaccess.cab"},
                            {".accde", "application/msaccess"},
                            {".accdr", "application/msaccess.runtime"},
                            {".accdt", "application/msaccess"},
                            {".accdw", "application/msaccess.webapplication"},
                            {".accft", "application/msaccess.ftemplate"},
                            {".acx", "application/internet-property-stream"},
                            {".AddIn", "text/xml"},
                            {".ade", "application/msaccess"},
                            {".adobebridge", "application/x-bridge-url"},
                            {".adp", "application/msaccess"},
                            {".ADT", "audio/vnd.dlna.adts"},
                            {".ADTS", "audio/aac"},
                            {".afm", "application/octet-stream"},
                            {".ai", "application/postscript"},
                            {".aif", "audio/aiff"},
                            {".aifc", "audio/aiff"},
                            {".aiff", "audio/aiff"},
                            {".air", "application/vnd.adobe.air-application-installer-package+zip"},
                            {".amc", "application/mpeg"},
                            {".anx", "application/annodex"},
                            {".apk", "application/vnd.android.package-archive"},
                            {".apng", "image/apng"},
                            {".application", "application/x-ms-application"},
                            {".art", "image/x-jg"},
                            {".asa", "application/xml"},
                            {".asax", "application/xml"},
                            {".ascx", "application/xml"},
                            {".asd", "application/octet-stream"},
                            {".asf", "video/x-ms-asf"},
                            {".ashx", "application/xml"},
                            {".asi", "application/octet-stream"},
                            {".asm", "text/plain"},
                            {".asmx", "application/xml"},
                            {".aspx", "application/xml"},
                            {".asr", "video/x-ms-asf"},
                            {".asx", "video/x-ms-asf"},
                            {".atom", "application/atom+xml"},
                            {".au", "audio/basic"},
                            {".avci", "image/avci"},
                            {".avcs", "image/avcs"},
                            {".avi", "video/x-msvideo"},
                            {".avif", "image/avif"},
                            {".avifs", "image/avif-sequence"},
                            {".axa", "audio/annodex"},
                            {".axs", "application/olescript"},
                            {".axv", "video/annodex"},
                            {".bas", "text/plain"},
                            {".bcpio", "application/x-bcpio"},
                            {".bin", "application/octet-stream"},
                            {".bmp", "image/bmp"},
                            {".c", "text/plain"},
                            {".cab", "application/octet-stream"},
                            {".caf", "audio/x-caf"},
                            {".calx", "application/vnd.ms-office.calx"},
                            {".cat", "application/vnd.ms-pki.seccat"},
                            {".cc", "text/plain"},
                            {".cd", "text/plain"},
                            {".cdda", "audio/aiff"},
                            {".cdf", "application/x-cdf"},
                            {".cer", "application/x-x509-ca-cert"},
                            {".cfg", "text/plain"},
                            {".chm", "application/octet-stream"},
                            {".class", "application/x-java-applet"},
                            {".clp", "application/x-msclip"},
                            {".cmd", "text/plain"},
                            {".cmx", "image/x-cmx"},
                            {".cnf", "text/plain"},
                            {".cod", "image/cis-cod"},
                            {".config", "application/xml"},
                            {".contact", "text/x-ms-contact"},
                            {".coverage", "application/xml"},
                            {".cpio", "application/x-cpio"},
                            {".cpp", "text/plain"},
                            {".crd", "application/x-mscardfile"},
                            {".crl", "application/pkix-crl"},
                            {".crt", "application/x-x509-ca-cert"},
                            {".cs", "text/plain"},
                            {".csdproj", "text/plain"},
                            {".csh", "application/x-csh"},
                            {".csproj", "text/plain"},
                            {".css", "text/css"},
                            {".csv", "text/csv"},
                            {".cur", "application/octet-stream"},
                            {".czx", "application/x-czx"},
                            {".cxx", "text/plain"},
                            {".dat", "application/octet-stream"},
                            {".datasource", "application/xml"},
                            {".dbproj", "text/plain"},
                            {".dcr", "application/x-director"},
                            {".def", "text/plain"},
                            {".deploy", "application/octet-stream"},
                            {".der", "application/x-x509-ca-cert"},
                            {".dgml", "application/xml"},
                            {".dib", "image/bmp"},
                            {".dif", "video/x-dv"},
                            {".dir", "application/x-director"},
                            {".disco", "text/xml"},
                            {".divx", "video/divx"},
                            {".dll", "application/x-msdownload"},
                            {".dll.config", "text/xml"},
                            {".dlm", "text/dlm"},
                            {".doc", "application/msword"},
                            {".docm", "application/vnd.ms-word.document.macroEnabled.12"},
                            {".docx", "application/vnd.openxmlformats-officedocument.wordprocessingml.document"},
                            {".dot", "application/msword"},
                            {".dotm", "application/vnd.ms-word.template.macroEnabled.12"},
                            {".dotx", "application/vnd.openxmlformats-officedocument.wordprocessingml.template"},
                            {".dsp", "application/octet-stream"},
                            {".dsw", "text/plain"},
                            {".dtd", "text/xml"},
                            {".dtsConfig", "text/xml"},
                            {".dv", "video/x-dv"},
                            {".dvi", "application/x-dvi"},
                            {".dwf", "drawing/x-dwf"},
                            {".dwg", "application/acad"},
                            {".dwp", "application/octet-stream"},
                            {".dxf", "application/x-dxf"},
                            {".dxr", "application/x-director"},
                            {".eml", "message/rfc822"},
                            {".emf", "image/emf"},
                            {".emz", "application/octet-stream"},
                            {".eot", "application/vnd.ms-fontobject"},
                            {".eps", "application/postscript"},
                            {".es", "application/ecmascript"},
                            {".etl", "application/etl"},
                            {".etx", "text/x-setext"},
                            {".evy", "application/envoy"},
                            {".exe", "application/vnd.microsoft.portable-executable"},
                            {".exe.config", "text/xml"},
                            {".f4v", "video/mp4"},
                            {".fdf", "application/vnd.fdf"},
                            {".fif", "application/fractals"},
                            {".filters", "application/xml"},
                            {".fla", "application/octet-stream"},
                            {".flac", "audio/flac"},
                            {".flr", "x-world/x-vrml"},
                            {".flv", "video/x-flv"},
                            {".fsscript", "application/fsharp-script"},
                            {".fsx", "application/fsharp-script"},
                            {".generictest", "application/xml"},
                            {".geojson", "application/geo+json"},
                            {".gif", "image/gif"},
                            {".gml", "application/gml+xml"},
                            {".gpx", "application/gpx+xml"},
                            {".group", "text/x-ms-group"},
                            {".gsm", "audio/x-gsm"},
                            {".gtar", "application/x-gtar"},
                            {".gz", "application/x-gzip"},
                            {".h", "text/plain"},
                            {".hdf", "application/x-hdf"},
                            {".hdml", "text/x-hdml"},
                            {".heic", "image/heic"},
                            {".heics", "image/heic-sequence"},
                            {".heif", "image/heif"},
                            {".heifs", "image/heif-sequence"},
                            {".hhc", "application/x-oleobject"},
                            {".hhk", "application/octet-stream"},
                            {".hhp", "application/octet-stream"},
                            {".hlp", "application/winhlp"},
                            {".hpp", "text/plain"},
                            {".hqx", "application/mac-binhex40"},
                            {".hta", "application/hta"},
                            {".htc", "text/x-component"},
                            {".htm", "text/html"},
                            {".html", "text/html"},
                            {".htt", "text/webviewhtml"},
                            {".hxa", "application/xml"},
                            {".hxc", "application/xml"},
                            {".hxd", "application/octet-stream"},
                            {".hxe", "application/xml"},
                            {".hxf", "application/xml"},
                            {".hxh", "application/octet-stream"},
                            {".hxi", "application/octet-stream"},
                            {".hxk", "application/xml"},
                            {".hxq", "application/octet-stream"},
                            {".hxr", "application/octet-stream"},
                            {".hxs", "application/octet-stream"},
                            {".hxt", "text/html"},
                            {".hxv", "application/xml"},
                            {".hxw", "application/octet-stream"},
                            {".hxx", "text/plain"},
                            {".i", "text/plain"},
                            {".ical", "text/calendar"},
                            {".icalendar", "text/calendar"},
                            {".ico", "image/x-icon"},
                            {".ics", "text/calendar"},
                            {".idl", "text/plain"},
                            {".ief", "image/ief"},
                            {".ifb", "text/calendar"},
                            {".iii", "application/x-iphone"},
                            {".inc", "text/plain"},
                            {".inf", "application/octet-stream"},
                            {".ini", "text/plain"},
                            {".inl", "text/plain"},
                            {".ins", "application/x-internet-signup"},
                            {".ipa", "application/x-itunes-ipa"},
                            {".ipg", "application/x-itunes-ipg"},
                            {".ipproj", "text/plain"},
                            {".ipsw", "application/x-itunes-ipsw"},
                            {".iqy", "text/x-ms-iqy"},
                            {".isp", "application/x-internet-signup"},
                            {".isma", "application/octet-stream"},
                            {".ismv", "application/octet-stream"},
                            {".ite", "application/x-itunes-ite"},
                            {".itlp", "application/x-itunes-itlp"},
                            {".itms", "application/x-itunes-itms"},
                            {".itpc", "application/x-itunes-itpc"},
                            {".IVF", "video/x-ivf"},
                            {".jar", "application/java-archive"},
                            {".java", "application/octet-stream"},
                            {".jck", "application/liquidmotion"},
                            {".jcz", "application/liquidmotion"},
                            {".jfif", "image/pjpeg"},
                            {".jnlp", "application/x-java-jnlp-file"},
                            {".jpb", "application/octet-stream"},
                            {".jpe", "image/jpeg"},
                            {".jpeg", "image/jpeg"},
                            {".jpg", "image/jpeg"},
                            {".js", "application/javascript"},
                            {".json", "application/json"},
                            {".jsx", "text/jscript"},
                            {".jsxbin", "text/plain"},
                            {".key", "application/vnd.apple.keynote"},
                            {".latex", "application/x-latex"},
                            {".library-ms", "application/windows-library+xml"},
                            {".lit", "application/x-ms-reader"},
                            {".loadtest", "application/xml"},
                            {".lpk", "application/octet-stream"},
                            {".lsf", "video/x-la-asf"},
                            {".lst", "text/plain"},
                            {".lsx", "video/x-la-asf"},
                            {".lzh", "application/octet-stream"},
                            {".m13", "application/x-msmediaview"},
                            {".m14", "application/x-msmediaview"},
                            {".m1v", "video/mpeg"},
                            {".m2t", "video/vnd.dlna.mpeg-tts"},
                            {".m2ts", "video/vnd.dlna.mpeg-tts"},
                            {".m2v", "video/mpeg"},
                            {".m3u", "audio/x-mpegurl"},
                            {".m3u8", "audio/x-mpegurl"},
                            {".m4a", "audio/m4a"},
                            {".m4b", "audio/m4b"},
                            {".m4p", "audio/m4p"},
                            {".m4r", "audio/x-m4r"},
                            {".m4v", "video/x-m4v"},
                            {".mac", "image/x-macpaint"},
                            {".mak", "text/plain"},
                            {".man", "application/x-troff-man"},
                            {".manifest", "application/x-ms-manifest"},
                            {".map", "text/plain"},
                            {".master", "application/xml"},
                            {".mbox", "application/mbox"},
                            {".mda", "application/msaccess"},
                            {".mdb", "application/x-msaccess"},
                            {".mde", "application/msaccess"},
                            {".mdp", "application/octet-stream"},
                            {".me", "application/x-troff-me"},
                            {".mfp", "application/x-shockwave-flash"},
                            {".mht", "message/rfc822"},
                            {".mhtml", "message/rfc822"},
                            {".mid", "audio/mid"},
                            {".midi", "audio/mid"},
                            {".mix", "application/octet-stream"},
                            {".mk", "text/plain"},
                            {".mk3d", "video/x-matroska-3d"},
                            {".mka", "audio/x-matroska"},
                            {".mkv", "video/x-matroska"},
                            {".mmf", "application/x-smaf"},
                            {".mno", "text/xml"},
                            {".mny", "application/x-msmoney"},
                            {".mod", "video/mpeg"},
                            {".mov", "video/quicktime"},
                            {".movie", "video/x-sgi-movie"},
                            {".mp2", "video/mpeg"},
                            {".mp2v", "video/mpeg"},
                            {".mp3", "audio/mpeg"},
                            {".mp4", "video/mp4"},
                            {".mp4v", "video/mp4"},
                            {".mpa", "video/mpeg"},
                            {".mpe", "video/mpeg"},
                            {".mpeg", "video/mpeg"},
                            {".mpf", "application/vnd.ms-mediapackage"},
                            {".mpg", "video/mpeg"},
                            {".mpp", "application/vnd.ms-project"},
                            {".mpv2", "video/mpeg"},
                            {".mqv", "video/quicktime"},
                            {".ms", "application/x-troff-ms"},
                            {".msg", "application/vnd.ms-outlook"},
                            {".msi", "application/octet-stream"},
                            {".mso", "application/octet-stream"},
                            {".mts", "video/vnd.dlna.mpeg-tts"},
                            {".mtx", "application/xml"},
                            {".mvb", "application/x-msmediaview"},
                            {".mvc", "application/x-miva-compiled"},
                            {".mxf", "application/mxf"},
                            {".mxp", "application/x-mmxp"},
                            {".nc", "application/x-netcdf"},
                            {".nsc", "video/x-ms-asf"},
                            {".numbers", "application/vnd.apple.numbers"},
                            {".nws", "message/rfc822"},
                            {".ocx", "application/octet-stream"},
                            {".oda", "application/oda"},
                            {".odb", "application/vnd.oasis.opendocument.database"},
                            {".odc", "application/vnd.oasis.opendocument.chart"},
                            {".odf", "application/vnd.oasis.opendocument.formula"},
                            {".odg", "application/vnd.oasis.opendocument.graphics"},
                            {".odh", "text/plain"},
                            {".odi", "application/vnd.oasis.opendocument.image"},
                            {".odl", "text/plain"},
                            {".odm", "application/vnd.oasis.opendocument.text-master"},
                            {".odp", "application/vnd.oasis.opendocument.presentation"},
                            {".ods", "application/vnd.oasis.opendocument.spreadsheet"},
                            {".odt", "application/vnd.oasis.opendocument.text"},
                            {".oga", "audio/ogg"},
                            {".ogg", "audio/ogg"},
                            {".ogv", "video/ogg"},
                            {".ogx", "application/ogg"},
                            {".one", "application/onenote"},
                            {".onea", "application/onenote"},
                            {".onepkg", "application/onenote"},
                            {".onetmp", "application/onenote"},
                            {".onetoc", "application/onenote"},
                            {".onetoc2", "application/onenote"},
                            {".opus", "audio/ogg"},
                            {".orderedtest", "application/xml"},
                            {".osdx", "application/opensearchdescription+xml"},
                            {".otf", "application/font-sfnt"},
                            {".otg", "application/vnd.oasis.opendocument.graphics-template"},
                            {".oth", "application/vnd.oasis.opendocument.text-web"},
                            {".otp", "application/vnd.oasis.opendocument.presentation-template"},
                            {".ots", "application/vnd.oasis.opendocument.spreadsheet-template"},
                            {".ott", "application/vnd.oasis.opendocument.text-template"},
                            {".oxps", "application/oxps"},
                            {".oxt", "application/vnd.openofficeorg.extension"},
                            {".p10", "application/pkcs10"},
                            {".p12", "application/x-pkcs12"},
                            {".p7b", "application/x-pkcs7-certificates"},
                            {".p7c", "application/pkcs7-mime"},
                            {".p7m", "application/pkcs7-mime"},
                            {".p7r", "application/x-pkcs7-certreqresp"},
                            {".p7s", "application/pkcs7-signature"},
                            {".pages", "application/vnd.apple.pages"},
                            {".pbm", "image/x-portable-bitmap"},
                            {".pcast", "application/x-podcast"},
                            {".pct", "image/pict"},
                            {".pcx", "application/octet-stream"},
                            {".pcz", "application/octet-stream"},
                            {".pdf", "application/pdf"},
                            {".pfb", "application/octet-stream"},
                            {".pfm", "application/octet-stream"},
                            {".pfx", "application/x-pkcs12"},
                            {".pgm", "image/x-portable-graymap"},
                            {".pic", "image/pict"},
                            {".pict", "image/pict"},
                            {".pkgdef", "text/plain"},
                            {".pkgundef", "text/plain"},
                            {".pko", "application/vnd.ms-pki.pko"},
                            {".pls", "audio/scpls"},
                            {".pma", "application/x-perfmon"},
                            {".pmc", "application/x-perfmon"},
                            {".pml", "application/x-perfmon"},
                            {".pmr", "application/x-perfmon"},
                            {".pmw", "application/x-perfmon"},
                            {".png", "image/png"},
                            {".pnm", "image/x-portable-anymap"},
                            {".pnt", "image/x-macpaint"},
                            {".pntg", "image/x-macpaint"},
                            {".pnz", "image/png"},
                            {".pot", "application/vnd.ms-powerpoint"},
                            {".potm", "application/vnd.ms-powerpoint.template.macroEnabled.12"},
                            {".potx", "application/vnd.openxmlformats-officedocument.presentationml.template"},
                            {".ppa", "application/vnd.ms-powerpoint"},
                            {".ppam", "application/vnd.ms-powerpoint.addin.macroEnabled.12"},
                            {".ppm", "image/x-portable-pixmap"},
                            {".pps", "application/vnd.ms-powerpoint"},
                            {".ppsm", "application/vnd.ms-powerpoint.slideshow.macroEnabled.12"},
                            {".ppsx", "application/vnd.openxmlformats-officedocument.presentationml.slideshow"},
                            {".ppt", "application/vnd.ms-powerpoint"},
                            {".pptm", "application/vnd.ms-powerpoint.presentation.macroEnabled.12"},
                            {".pptx", "application/vnd.openxmlformats-officedocument.presentationml.presentation"},
                            {".prf", "application/pics-rules"},
                            {".prm", "application/octet-stream"},
                            {".prx", "application/octet-stream"},
                            {".ps", "application/postscript"},
                            {".psc1", "application/PowerShell"},
                            {".psd", "application/octet-stream"},
                            {".psess", "application/xml"},
                            {".psm", "application/octet-stream"},
                            {".psp", "application/octet-stream"},
                            {".pst", "application/vnd.ms-outlook"},
                            {".pub", "application/x-mspublisher"},
                            {".pwz", "application/vnd.ms-powerpoint"},
                            {".qht", "text/x-html-insertion"},
                            {".qhtm", "text/x-html-insertion"},
                            {".qt", "video/quicktime"},
                            {".qti", "image/x-quicktime"},
                            {".qtif", "image/x-quicktime"},
                            {".qtl", "application/x-quicktimeplayer"},
                            {".qxd", "application/octet-stream"},
                            {".ra", "audio/x-pn-realaudio"},
                            {".ram", "audio/x-pn-realaudio"},
                            {".rar", "application/x-rar-compressed"},
                            {".ras", "image/x-cmu-raster"},
                            {".rat", "application/rat-file"},
                            {".rc", "text/plain"},
                            {".rc2", "text/plain"},
                            {".rct", "text/plain"},
                            {".rdlc", "application/xml"},
                            {".reg", "text/plain"},
                            {".resx", "application/xml"},
                            {".rf", "image/vnd.rn-realflash"},
                            {".rgb", "image/x-rgb"},
                            {".rgs", "text/plain"},
                            {".rm", "application/vnd.rn-realmedia"},
                            {".rmi", "audio/mid"},
                            {".rmp", "application/vnd.rn-rn_music_package"},
                            {".rmvb", "application/vnd.rn-realmedia-vbr"},
                            {".roff", "application/x-troff"},
                            {".rpm", "audio/x-pn-realaudio-plugin"},
                            {".rqy", "text/x-ms-rqy"},
                            {".rtf", "application/rtf"},
                            {".rtx", "text/richtext"},
                            {".rvt", "application/octet-stream"},
                            {".ruleset", "application/xml"},
                            {".s", "text/plain"},
                            {".safariextz", "application/x-safari-safariextz"},
                            {".scd", "application/x-msschedule"},
                            {".scr", "text/plain"},
                            {".sct", "text/scriptlet"},
                            {".sd2", "audio/x-sd2"},
                            {".sdp", "application/sdp"},
                            {".sea", "application/octet-stream"},
                            {".searchConnector-ms", "application/windows-search-connector+xml"},
                            {".setpay", "application/set-payment-initiation"},
                            {".setreg", "application/set-registration-initiation"},
                            {".settings", "application/xml"},
                            {".sgimb", "application/x-sgimb"},
                            {".sgml", "text/sgml"},
                            {".sh", "application/x-sh"},
                            {".shar", "application/x-shar"},
                            {".shtml", "text/html"},
                            {".sit", "application/x-stuffit"},
                            {".sitemap", "application/xml"},
                            {".skin", "application/xml"},
                            {".skp", "application/x-koan"},
                            {".sldm", "application/vnd.ms-powerpoint.slide.macroEnabled.12"},
                            {".sldx", "application/vnd.openxmlformats-officedocument.presentationml.slide"},
                            {".slk", "application/vnd.ms-excel"},
                            {".sln", "text/plain"},
                            {".slupkg-ms", "application/x-ms-license"},
                            {".smd", "audio/x-smd"},
                            {".smi", "application/octet-stream"},
                            {".smx", "audio/x-smd"},
                            {".smz", "audio/x-smd"},
                            {".snd", "audio/basic"},
                            {".snippet", "application/xml"},
                            {".snp", "application/octet-stream"},
                            {".sql", "application/sql"},
                            {".sol", "text/plain"},
                            {".sor", "text/plain"},
                            {".spc", "application/x-pkcs7-certificates"},
                            {".spl", "application/futuresplash"},
                            {".spx", "audio/ogg"},
                            {".src", "application/x-wais-source"},
                            {".srf", "text/plain"},
                            {".SSISDeploymentManifest", "text/xml"},
                            {".ssm", "application/streamingmedia"},
                            {".sst", "application/vnd.ms-pki.certstore"},
                            {".stl", "application/vnd.ms-pki.stl"},
                            {".sv4cpio", "application/x-sv4cpio"},
                            {".sv4crc", "application/x-sv4crc"},
                            {".svc", "application/xml"},
                            {".svg", "image/svg+xml"},
                            {".swf", "application/x-shockwave-flash"},
                            {".step", "application/step"},
                            {".stp", "application/step"},
                            {".t", "application/x-troff"},
                            {".tar", "application/x-tar"},
                            {".tcl", "application/x-tcl"},
                            {".testrunconfig", "application/xml"},
                            {".testsettings", "application/xml"},
                            {".tex", "application/x-tex"},
                            {".texi", "application/x-texinfo"},
                            {".texinfo", "application/x-texinfo"},
                            {".tgz", "application/x-compressed"},
                            {".thmx", "application/vnd.ms-officetheme"},
                            {".thn", "application/octet-stream"},
                            {".tif", "image/tiff"},
                            {".tiff", "image/tiff"},
                            {".tlh", "text/plain"},
                            {".tli", "text/plain"},
                            {".toc", "application/octet-stream"},
                            {".tr", "application/x-troff"},
                            {".trm", "application/x-msterminal"},
                            {".trx", "application/xml"},
                            {".ts", "video/vnd.dlna.mpeg-tts"},
                            {".tsv", "text/tab-separated-values"},
                            {".ttf", "application/font-sfnt"},
                            {".tts", "video/vnd.dlna.mpeg-tts"},
                            {".txt", "text/plain"},
                            {".u32", "application/octet-stream"},
                            {".uls", "text/iuls"},
                            {".user", "text/plain"},
                            {".ustar", "application/x-ustar"},
                            {".vb", "text/plain"},
                            {".vbdproj", "text/plain"},
                            {".vbk", "video/mpeg"},
                            {".vbproj", "text/plain"},
                            {".vbs", "text/vbscript"},
                            {".vcf", "text/x-vcard"},
                            {".vcproj", "application/xml"},
                            {".vcs", "text/plain"},
                            {".vcxproj", "application/xml"},
                            {".vddproj", "text/plain"},
                            {".vdp", "text/plain"},
                            {".vdproj", "text/plain"},
                            {".vdx", "application/vnd.ms-visio.viewer"},
                            {".vml", "text/xml"},
                            {".vscontent", "application/xml"},
                            {".vsct", "text/xml"},
                            {".vsd", "application/vnd.visio"},
                            {".vsdx", "application/vnd.ms-visio.viewer"},
                            {".vsi", "application/ms-vsi"},
                            {".vsix", "application/vsix"},
                            {".vsixlangpack", "text/xml"},
                            {".vsixmanifest", "text/xml"},
                            {".vsmdi", "application/xml"},
                            {".vspscc", "text/plain"},
                            {".vss", "application/vnd.visio"},
                            {".vsscc", "text/plain"},
                            {".vssettings", "text/xml"},
                            {".vssscc", "text/plain"},
                            {".vst", "application/vnd.visio"},
                            {".vstemplate", "text/xml"},
                            {".vsto", "application/x-ms-vsto"},
                            {".vsw", "application/vnd.visio"},
                            {".vsx", "application/vnd.visio"},
                            {".vtt", "text/vtt"},
                            {".vtx", "application/vnd.visio"},
                            {".wasm", "application/wasm"},
                            {".wav", "audio/wav"},
                            {".wave", "audio/wav"},
                            {".wax", "audio/x-ms-wax"},
                            {".wbk", "application/msword"},
                            {".wbmp", "image/vnd.wap.wbmp"},
                            {".wcm", "application/vnd.ms-works"},
                            {".wdb", "application/vnd.ms-works"},
                            {".wdp", "image/vnd.ms-photo"},
                            {".webarchive", "application/x-safari-webarchive"},
                            {".webm", "video/webm"},
                            {".webp", "image/webp"}, /* https://en.wikipedia.org/wiki/WebP */
                            {".webtest", "application/xml"},
                            {".wiq", "application/xml"},
                            {".wiz", "application/msword"},
                            {".wks", "application/vnd.ms-works"},
                            {".WLMP", "application/wlmoviemaker"},
                            {".wlpginstall", "application/x-wlpg-detect"},
                            {".wlpginstall3", "application/x-wlpg3-detect"},
                            {".wm", "video/x-ms-wm"},
                            {".wma", "audio/x-ms-wma"},
                            {".wmd", "application/x-ms-wmd"},
                            {".wmf", "application/x-msmetafile"},
                            {".wml", "text/vnd.wap.wml"},
                            {".wmlc", "application/vnd.wap.wmlc"},
                            {".wmls", "text/vnd.wap.wmlscript"},
                            {".wmlsc", "application/vnd.wap.wmlscriptc"},
                            {".wmp", "video/x-ms-wmp"},
                            {".wmv", "video/x-ms-wmv"},
                            {".wmx", "video/x-ms-wmx"},
                            {".wmz", "application/x-ms-wmz"},
                            {".woff", "application/font-woff"},
                            {".woff2", "application/font-woff2"},
                            {".wpl", "application/vnd.ms-wpl"},
                            {".wps", "application/vnd.ms-works"},
                            {".wri", "application/x-mswrite"},
                            {".wrl", "x-world/x-vrml"},
                            {".wrz", "x-world/x-vrml"},
                            {".wsc", "text/scriptlet"},
                            {".wsdl", "text/xml"},
                            {".wvx", "video/x-ms-wvx"},
                            {".x", "application/directx"},
                            {".xaf", "x-world/x-vrml"},
                            {".xaml", "application/xaml+xml"},
                            {".xap", "application/x-silverlight-app"},
                            {".xbap", "application/x-ms-xbap"},
                            {".xbm", "image/x-xbitmap"},
                            {".xdr", "text/plain"},
                            {".xht", "application/xhtml+xml"},
                            {".xhtml", "application/xhtml+xml"},
                            {".xla", "application/vnd.ms-excel"},
                            {".xlam", "application/vnd.ms-excel.addin.macroEnabled.12"},
                            {".xlc", "application/vnd.ms-excel"},
                            {".xld", "application/vnd.ms-excel"},
                            {".xlk", "application/vnd.ms-excel"},
                            {".xll", "application/vnd.ms-excel"},
                            {".xlm", "application/vnd.ms-excel"},
                            {".xls", "application/vnd.ms-excel"},
                            {".xlsb", "application/vnd.ms-excel.sheet.binary.macroEnabled.12"},
                            {".xlsm", "application/vnd.ms-excel.sheet.macroEnabled.12"},
                            {".xlsx", "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"},
                            {".xlt", "application/vnd.ms-excel"},
                            {".xltm", "application/vnd.ms-excel.template.macroEnabled.12"},
                            {".xltx", "application/vnd.openxmlformats-officedocument.spreadsheetml.template"},
                            {".xlw", "application/vnd.ms-excel"},
                            {".xml", "text/xml"},
                            {".xmp", "application/octet-stream"},
                            {".xmta", "application/xml"},
                            {".xof", "x-world/x-vrml"},
                            {".XOML", "text/plain"},
                            {".xpm", "image/x-xpixmap"},
                            {".xps", "application/vnd.ms-xpsdocument"},
                            {".xrm-ms", "text/xml"},
                            {".xsc", "application/xml"},
                            {".xsd", "text/xml"},
                            {".xsf", "text/xml"},
                            {".xsl", "text/xml"},
                            {".xslt", "text/xml"},
                            {".xsn", "application/octet-stream"},
                            {".xss", "application/xml"},
                            {".xspf", "application/xspf+xml"},
                            {".xtp", "application/octet-stream"},
                            {".xwd", "image/x-xwindowdump"},
                            {".yml", "application/yaml"},
                            {".yaml", "application/yaml"},
                            {".z", "application/x-compress"},
                            {".zip", "application/zip"},

                            {"application/fsharp-script", ".fsx"},
                            {"application/msaccess", ".adp"},
                            {"application/msword", ".doc"},
                            {"application/octet-stream", ".bin"},
                            {"application/onenote", ".one"},
                            {"application/postscript", ".eps"},
                            {"application/step", ".step"},
                            {"application/vnd.apple.keynote", ".key"},
                            {"application/vnd.apple.numbers", ".numbers"},
                            {"application/vnd.apple.pages", ".pages"},
                            {"application/vnd.ms-excel", ".xls"},
                            {"application/vnd.ms-powerpoint", ".ppt"},
                            {"application/vnd.ms-works", ".wks"},
                            {"application/vnd.visio", ".vsd"},
                            {"application/x-director", ".dir"},
                            {"application/x-msdos-program", ".exe"},
                            {"application/x-shockwave-flash", ".swf"},
                            {"application/x-x509-ca-cert", ".cer"},
                            {"application/x-zip-compressed", ".zip"},
                            {"application/xhtml+xml", ".xhtml"},
                            {"application/x-iwork-keynote-sffkey", ".key"},
                            {"application/x-iwork-numbers-sffnumbers", ".numbers"},
                            {"application/x-iwork-pages-sffpages", ".pages"},
                            {"application/xml", ".xml"}, // anomaly, .xml -> text/xml, but application/xml -> many things, but all are xml, so safest is .xml
                            {"audio/aac", ".AAC"},
                            {"audio/aiff", ".aiff"},
                            {"audio/basic", ".snd"},
                            {"audio/mid", ".midi"},
                            {"audio/mp4", ".m4a"}, // one way mapping only, mime -> ext
                            {"audio/ogg", ".ogg"},
                            {"audio/ogg; codecs=opus", ".opus"},
                            {"audio/wav", ".wav"},
                            {"audio/x-m4a", ".m4a"},
                            {"audio/x-mpegurl", ".m3u"},
                            {"audio/x-pn-realaudio", ".ra"},
                            {"audio/x-smd", ".smd"},
                            {"image/bmp", ".bmp"},
                            {"image/heic", ".heic"},
                            {"image/heif", ".heif"},
                            {"image/jpeg", ".jpg"},
                            {"image/pict", ".pic"},
                            {"image/png", ".png"}, // Defined in [RFC-2045], [RFC-2048]
                            {"image/x-png", ".png"}, // See https://www.w3.org/TR/PNG/#A-Media-type :"It is recommended that implementations also recognize the media type "image/x-png"."
                            {"image/tiff", ".tiff"},
                            {"image/x-macpaint", ".mac"},
                            {"image/x-quicktime", ".qti"},
                            {"message/rfc822", ".eml"},
                            {"text/calendar", ".ics"},
                            {"text/html", ".html"},
                            {"text/plain", ".txt"},
                            {"text/scriptlet", ".wsc"},
                            {"text/xml", ".xml"},
                            {"video/3gpp", ".3gp"},
                            {"video/3gpp2", ".3gp2"},
                            {"video/mp4", ".mp4"},
                            {"video/mpeg", ".mpg"},
                            {"video/quicktime", ".mov"},
                            {"video/vnd.dlna.mpeg-tts", ".m2t"},
                            {"video/x-dv", ".dv"},
                            {"video/x-la-asf", ".lsf"},
                            {"video/x-ms-asf", ".asf"},
                            {"x-world/x-vrml", ".xof"},

                            #endregion

                            };

            var cache = mappings.ToList(); // need ToList() to avoid modifying while still enumerating

            foreach (var mapping in cache)
            {
                if (!mappings.ContainsKey(mapping.Value))
                {
                    mappings.Add(mapping.Value, mapping.Key);
                }
            }

            return mappings;
        }

        /// <summary>
        /// Tries to get the MIME type from the provided string.
        /// </summary>
        /// <param name="str">The filename or extension.</param>
        /// <param name="mimeType">The variable to store the MIME type.</param>
        /// <returns>True if the MIME type was found; otherwise, false.</returns>
        /// <exception cref="ArgumentNullException"/>
        public static bool TryGetMimeType(string str, out string mimeType)
        {
            if (str == null)
            {
                throw new ArgumentNullException(nameof(str));
            }

            var indexQuestionMark = str.IndexOf(QuestionMark, StringComparison.Ordinal);
            if (indexQuestionMark != -1)
            {
                str = str.Remove(indexQuestionMark);
            }


            if (!str.StartsWith(Dot))
            {
                var index = str.LastIndexOf(Dot);
                if (index != -1 && str.Length > index + 1)
                {
                    str = str.Substring(index + 1);
                }

                str = Dot + str;
            }

            return _mappings.Value.TryGetValue(str, out mimeType!);
        }

        /// <summary>
        /// Gets the MIME type from the provided string.
        /// </summary>
        /// <param name="str">The filename or extension.</param>
        /// <returns>The MIME type if found; otherwise, the default MIME type.</returns>
        /// <exception cref="ArgumentNullException"/>
        public static string GetMimeType(string str)
        {
            return MimeTypeMap.TryGetMimeType(str, out var result) ? result : DefaultMimeType;
        }

        /// <summary>
        /// Gets the file extension from the provided MIME type.
        /// </summary>
        /// <param name="mimeType">The MIME type.</param>
        /// <param name="throwErrorIfNotFound">If true, throws an error if the extension is not found.</param>
        /// <returns>The file extension.</returns>
        /// <exception cref="ArgumentNullException"/>
        /// <exception cref="ArgumentException"/>
        public static string GetExtension(string mimeType, bool throwErrorIfNotFound = true)
        {
            if (mimeType == null)
            {
                throw new ArgumentNullException(nameof(mimeType));
            }

            if (mimeType.StartsWith(Dot))
            {
                throw new ArgumentException("Requested mime type is not valid: " + mimeType);
            }

            if (_mappings.Value.TryGetValue(mimeType, out string? extension))
            {
                return extension;
            }

            if (throwErrorIfNotFound)
            {
                throw new ArgumentException("Requested mime type is not registered: " + mimeType);
            }

            return string.Empty;
        }
    }


    #endregion

    /// <summary>
    /// Gets the URI scheme handled by this resource handler.
    /// </summary>
    public abstract string Scheme { get; }
    /// <summary>
    /// Gets the host name handled by this resource handler.
    /// </summary>
    public abstract string HostName { get; }
    /// <summary>
    /// Gets the web resource context for this handler.
    /// </summary>
    public abstract CoreWebView2WebResourceContext WebResourceContext { get; }

    /// <summary>
    /// Gets the default file names to use when a directory is requested.
    /// </summary>
    public virtual string[] DefaultFileName { get; } = ["index.html", "index.htm", "default.html"];

    /// <summary>
    /// Gets the base URI for this handler.
    /// </summary>
    public Uri Uri => new Uri($"{Scheme}://{HostName}".ToLower());

    /// <summary>
    /// Gets a value indicating whether the scheme is a standard web scheme.
    /// </summary>
    public bool IsStandardScheme
    {
        get
        {
            return (Scheme?.ToLower()) switch
            {
                "http" or "https" or "file" or "ftp" or "about" or "data" => true,
                _ => false,
            };
        }
    }

    const string DEFAULT_MIME_TYPE = "application/octet-stream";

    /// <summary>
    /// Gets the MIME type for the specified file name.
    /// </summary>
    /// <param name="fileName">The file name.</param>
    /// <returns>The MIME type if found; otherwise, the default MIME type.</returns>
    protected static string GetMimeType(string fileName)
    {
        var ext = Path.GetExtension(fileName)?.Trim('.') ?? string.Empty;

        if (string.IsNullOrEmpty(ext))
        {
            return DEFAULT_MIME_TYPE;
        }

        return MimeTypeMap.GetMimeType(ext);
    }

    /// <summary>
    /// When implemented in a derived class, returns a <see cref="WebResourceResponse"/> for the given request.
    /// </summary>
    /// <param name="request">The web resource request.</param>
    /// <returns>A <see cref="WebResourceResponse"/> instance, or null if not found.</returns>
    abstract protected WebResourceResponse GetResourceResponse(WebResourceRequest request);

    /// <summary>
    /// Initializes a new instance of the <see cref="WebResourceHandler"/> class.
    /// </summary>
    public WebResourceHandler()
    {

    }

    /// <summary>
    /// Handles a web resource request and sets the response on the event arguments.
    /// </summary>
    /// <param name="webview">The WebView2 control instance.</param>
    /// <param name="args">The event arguments for the web resource request.</param>
    internal void HandleRequest(CoreWebView2 webview, CoreWebView2WebResourceRequestedEventArgs args)
    {
        //var deferral = args.GetDeferral();


        try
        {
            //using var response = await Task.Run(() => GetResourceResponse(new WebResourceRequest(args.Request, args.RequestedSourceKind, WebResourceContext)));

            var response = GetResourceResponse(new WebResourceRequest(args.Request, args.RequestedSourceKind, WebResourceContext));

            if (response == null)
            {
                args.Response = webview.Environment.CreateWebResourceResponse(null, StatusCodes.Status404NotFound, "Not Found", string.Empty);
                return;
            }

            string? headers = null;

            headers = string.Join(";", response.Headers.AllKeys.Select(key => key + ": " + response.Headers[key]).ToArray()) ?? string.Empty;

            args.Response = webview.Environment.CreateWebResourceResponse(response.ContentBody is null ? null : new ManagedStream(response.ContentBody), response.HttpStatus, StatusCodes.GetStatusPhrase(response.HttpStatus), headers);
        }
        catch (Exception ex)
        {
            args.Response = webview.Environment.CreateWebResourceResponse(null, StatusCodes.Status500InternalServerError, ex.Message, string.Empty);

        }
        //finally
        //{
        //    deferral.Complete();
        //}


    }


}
